1856.] HARKNESS LOWEST ROCKS OF ESKDALE. 243 



tail being dragged along the ground. On each side of this central 

 line we have a regular series of other lines, of a more complex nature, 

 arranged almost at right angles to the cen- t^. ^ ^ 

 tral line; these are about the one-fifth of Fig- 2.— Impression on 

 an inch in length, and the nearest of these ^^^ surface o/ the 

 lines to the central one is at about the di- fiy^tone at Binks, 

 stance of its length, viz. one-fifth of an inch. Rowhurghshire. (Na- 

 These lateral lines, which are somewhat tural size.; 

 broken, and arranged at nearly right angles ^ 



to the centre one, are broader and deeper at ** * f ^ * « 



their extremities ; and outside of them there I 



is seen, slightly before each, a small pitted 

 hole about the size of a pin's head. These «~ 

 lateral linear impressions appear to have been 

 produced by legs, and the holes near their 

 extremities seem to have arisen from joints, c— 

 while the small hole in front looks like the 

 markings caused by the tip of the leg. If 

 these markings have resulted from Crusta- 

 ceans, they afford us proof of the very early 

 existence of Crustaceans with feet. <^- 





^, ^#^ ^"^ 



[Note on the Fossil Track from Binks, 

 by Mr. Salter. — We may apply to this im- 

 print — which through Mr. Harkness's kind- 

 ness I have had full opportunity of study- 

 ing — the name of Protichnites scoticus. 



The imposition of this generic name does not in any way imply 

 that the creature which made the track was generically identical 

 with those which produced the tracks in the Potsdam sandstone, 

 and which Professor Owen has so well described *. On the con- 

 trary, there are some differences of importance, indicating, as I think, 

 that a single pair only of members (in addition to the median ridge 

 of the body) were employed in making the impression ; whilst in the 

 Canadian tracks there were (according to Prof. Owen) certainly three, 

 four, or five pairs ; or, if (as appears to me most probable) each im- 

 pression was made by its own independent limb, seven or eight pairs 

 of such members may be supposed to have existed. 



The inner and double imprints, a a, are all so closely like each 

 other, and so much of the same size, as to indicate that the same in- 

 strument produced them in succession ; and the smaller indents, c, 

 are not so unlike but that they might have been also impressed by 

 the tip of the same weapon in different positions. They were pro- 

 bably made (assuming that the creature was a Crustacean, as is most 

 Hkely) by the basal joint or joints of a bent limb, or swimming 

 foot ; while the single indents, b b, not always present, might be made 

 by the tip of the same limb during each stroke. These strokes appear 

 to have been given at first at a greater distance from the central hne 

 or track (e) than the latter ones, which have gradually converged 



* Quart. Journ. Geol. Soc. vol. viii. p. 214. 



